XDocument and Linq returns null if the element has

Newbie with XDocuments and Linq, please suggest a solution to retrieve the data from a particular tag in the xml string:

If I have a XML string from webservice response (I formatted xml for ease):

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <soap:Body>
    <GetCashFlowReportResponse xmlns="http://tempuri.org/">
      <GetCashFlowReportPdf>Hello!</GetCashFlowReportPdf>
    </GetCashFlowReportResponse>
  </soap:Body>
</soap:Envelope>

Using the following code, I can get the value only if GetCashFlowReportResponse tag doesn't have "xmlns" attribute. Not sure why? Otherwise, it always return null.

string inputString = "<?xml version=\"1.0\" encoding=\"utf-8\"?><soap:Envelope xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\"><soap:Body><GetCashFlowReportResponse xmlns=\"http://tempuri.org/\"><GetCashFlowReportPdf>Hello!</GetCashFlowReportPdf></GetCashFlowReportResponse></soap:Body></soap:Envelope>"    
XDocument xDoc = XDocument.Parse(inputString);
//XNamespace ns = "http://tempuri.org/";
XNamespace ns = XNamespace.Get("http://tempuri.org/");

var data = from c in xDoc.Descendants(ns + "GetCashFlowReportResponse")
           select (string)c.Element("GetCashFlowReportPdf");

foreach (string val in data)
{
    Console.WriteLine(val);
}

I can't change the web service to remove that attribute. IS there a better way to read the response and get the actual data back to the user (in more readable form)?

Edited: SOLUTION:

XDocument xDoc = XDocument.Parse(inputString);
XNamespace ns = "http://tempuri.org/";

var data = from c in xDoc.Descendants(ns + "GetCashFlowReportResponse")
           select (string)c.Element(ns + "GetCashFlowReportPdf");
foreach (string val in data)
{
   Console.WriteLine(val);
}

Note: Even if all the child elements doesn't have the namespace attribute, the code will work if you add the "ns" to the element as I guess childs inherit the namespace from parent (see response from SLaks).

回答1:

You need to include the namespace:

XNamespace ns = "http://tempuri.org/";

xDoc.Descendants(ns + "GetCashFlowReportResponse")

回答2:

XName qualifiedName = XName.Get("GetCashFlowReportResponse", 
    "http://tempuri.org/");

var data = from d in xDoc.Descendants(qualifiedName)

回答3:

Just ask for the elements using the qualified names:

// create a XML namespace object
XNamespace ns = XNamespace.Get("http://tempuri.org/");

var data = from c in xDoc.Descendants(ns + "GetCashFlowReportResponse")
           select (string)c.Element(ns + "GetCashFlowReportPdf");

Note the use of the overloaded + operator that creates a QName with a XML namespace and a local name string.